Printed circuit board connector

ABSTRACT

A printed circuit board connector having a plurality of contacts mounted in the connector housing and the method of assembly thereof. The contacts are formed of a spring contact portion having a contacting surface and terminal portions interconnected by a central mounting portion. The contact is inserted on a mounting member in an unstressed condition with the contacting surface extending from the mounting member in one direction and the terminal portion extending from the mounting member in an opposite direction. A connector housing member contains a slot therethrough for positioning a printed circuit board therein. The connector housing member is positioned on the mounting member. When positioned on the member, curved inner surfaces of the housing member cause the contacts to be spread apart, preloading the contacts at the tip. When the printed circuit board is inserted into the housing, the housing protects the tip member from direct contact by the printed circuit board.

United States Patent 91 Mattingly, Jr. et al. 45 June 5, 1973 [54]PRINTED CIRCUIT BOARD Primary Examiner-Marvin A. Champion CONNECTORAssistant Examiner-Lawrence J. Staab [75] Inventors: William Russell g,Attorney-C. Cornell Remsen, .lr., Walter J. Baum,

[73] Assignee: International Telephone and Telegraph Corporation, NewYork, NY.

[22] Filed: Nov. 17, 1971 [21] Appl. No.: 199,470

[52] U.S. Cl ..339/l86 M, 339/17 L, 339/176 MP [51] Int. Cl ..H05k 1/07,l-lOlr 13/64 [58] Field of Search ..339/17 L, 17 LM, 339/75 MP, 176 MP,184 M, 186 M [56] References Cited UNITED STATES PATENTS 3,395,3777/1968 Straus ..339/l7 L 3,464,054 8/1969 Mansfield ...339/176 MP3,671,917 6/1972 Ammon et al. ..339/17 L 3,008,113 Johnson ..339/l76 MPSanta Ana; Peter Michael Gregson, Redondo Beach, both of Calif.

A connector housing member contains a Paul l-lemminger et al.

[57] ABSTRACT A printed circuit board connector having a plurality ofcontacts mounted in the connector housing and the method of assemblythereof. The contacts are formed of a spring contact portion having acontacting surface and terminal portions interconnected by a centralmounting portion. The contact is inserted on a mounting member in anunstressed condition with the contacting surface extending from themounting member in one direction and the terminal portion extending fromthe mounting member in an opposite direction. slot therethrough forpositioning a printed circuit board therein. The connector housingmember is positioned on the mounting member. When positioned on themember, curved inner surfaces of the housing member cause the contactsto be spread apart, preloading the contacts at the tip. When the printedcircuit board is inserted into the housing, the housing protects the tipmember from direct contact by the printed circuit board.

3 Claims, 4 Drawing Figures Patented June 5, 1973 1 PRINTED CIRCUITBOARD CONNECTOR BACKGROUND OF THE INVENTION Conventional printed circuitboard connectors utilized contacts to electrically connect printedcircuit board connectors to a printed circuit board. Typically, thecontacts are mounted on a base member or the connector housing, and arepreloaded at the base of the contact or at the tip of the contact, nearthe entry in the connector housing, where the printed circuit boardenters the housing. To prevent damage at the tip of the contact, it isnecessary to protect the contact tip so that when an external force,such as a printed circuit board, is applied to the connector, the tipdoes not touch the printed circuit board.

In one form of preloaded printed circuit board contacts, the contactsare press-fitted into the plate through holes of a multilayer boardwhich leaves the contacts in an upright position. The connectorinsulator is then assembled over the top of the contacts, and thecontacts are fully deflected by a molded-in middle card stop web. Whenthe insulator is flush to the multilayer board, the base of the contactpresses firmly against the edge of the card stop, preloading thecontacts as well as retaining the insulator to the multilayer board. Insuch an arrangement, full deflection of the contacts is necessary tofully assemble the insulator. Such deflection causes stress to thepress-fit portion of the contact in the plated through hole of the boardbefore the insulator is fully assembled. Moreover, each time a printedcircuit board is inserted, the same stress occurs. Moreover, in such anarrangement, the tips of the contacts are exposed since the insulatordoes not have a closed entry arrangement.

In an alternative form of tip loaded printed circuit board connectors,aprinted circuit board is inserted between the contacts prior to mountingthe connector insulator on the portion multilayer board, having thepress-fit contacts thereon. After the contacts have been spread apartbetween the printed circuit board, the insulator is positioned on thecontacts and the tips of the contacts are lodged behind pads molded inthe insulator on either side of an insulator slot. Then, the printedcircuit board can be removed and the contacts remain preloaded at theirtips. The need for a printed circuit board or tool to deflect thecontacts before full insulator assembly can be made, results in acumbersome assembly. Further, it is necessary to deflect the contacts anamount greater than the preloaded condition, thus causing possibleoverstress to the contacts, should the insulator be mounted on theassembly at an angle.

In order to overcome the attendant disadvantages of prior art printedcircuit board connectors, which are preloaded at their tip, the presentinvention eliminates the need for a board or tool to deflect thecontacts prior to insertion of the insulator housing. In the presentinvention, the connector insulator housing is affixed to the bottom ofeach contact so as to align the insulator prior to displacement of thecontacts, as preloading of the contacts occurs. The insulator housingitself, when fully pressed down and retained by the interference of eachcontact to each cavity, provides automatic preloading of the contact atthe tip. Moreover, the insulator provides closed entry at its engagingend so that the tips of all contacts are protected from damage from theinsertion of foreign instruments.

The advantages of the invention, both as to its construction and mode ofoperation, will be readily appreciated as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings in which likereferenced numerals designate like parts throughout the figures.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an exploded perspectiveview, partly in cross-section, of the printed circuit board connectorshowing the position of the connector members prior to assembly;

FIG. 2 illustrates a cross-sectional view of the printed circuit boardconnector shown in FIG. 1 with the insulator member partially mountedthereon;

FIG. 3 shows a cross-sectional view of the printed circuit boardconnector of FIGS. 1 and 2 fully assembled; and

FIG. 4 depicts the printed circuit board of FIGS. 1 through 3 with aprinted circuit board inserted therein.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,there is shown in FIG. 1 an exploded perspective view partly in sectionof the electrical connector assembly made in accordance with theprinciples of the invention. The connector assembly comprises aninsulator mounting member 12 having a plurality of bores 14extendingperpendicularly therethrough. Adapted to be positioned in eachof the bores are a plurality of electrical contacts 16. The contacts 16are formed of a terminal portion 18 and a spring contact portion 22,with the portions 18 and 22 being interconnected by a central mountingportion 24. The contacts 16 are preferably stamped from suitable metalstock to provide the desired strength.

The terminal portion 18 is generally square in crosssection and may betapered as at its tip end 26 to facilitate insertion of the contact intothe bores 14. The spring contact portion is shown as being bifurcated bymeans ofa slot 28 which opens at the tip end 30 to provide redundantcontact points to a conductor which is positioned on a printed circuitboard, as well as a multiple frequency of vibrations since each portionis not identical. The spring portion 22 contains a shank end 32 whichinterconnects the mounting portion 24 to the bifurcated end of thecontact. Normally, the spring portiocan be tapered from the shank end 32to the outer tip end 30 of the spring portion to provide a betterdistribution of the stress therealong. The spring portion 22 is firstbent in a first direction at the shank end 32 and then reverse bent inthe opposite direction as at section 34 in the vicinity of the slot 28,with the section 36 defining the junction of the shank end 32 andsection 34.

The central mounting portion 24 which interconnects the shank end 32 andthe terminal portion 18, is of an approximately equal thickness as theseparts at its junctions therewith. However, the mounting portion isslightly wider than the shank end 32 at the junction so as to define anupwardly facing shoulder 38. At its junction, with the terminal portion18, a tapered transitional section 42 provides the width transitionbetween the terminal portion 18 and the lower end 44 of the mountingportion. The lower end 44 of the mounting portion is not as wide as theupper end 46 of the mounting portion, and a downwardly facing shoulder48 thereby defines the intersection of the upper and lower ends 44 and46 of the mounting portion. The width of the lower end 44 isapproximately equal to the diameter of the bores 14 so that when thecontacts 16 are inserted into the bores 14, the shoulder 48 will rest onthe top surface of the mounting member 12, correctly positioning thecontacts thereon. As shown in FIG. 2, the contacts 16 are mounted inpairs of rows, and prior to positioning of an insulating member 62thereon, the section 36 of adjacent contacts touch, or nearly touch eachother.

Referring once again to FIG. 1, the insulating housing member 62comprises a pair of side walls 64 and end walls 66. Normally, the endwall structure 66 is of greater height than the side walls. The sidewalls 64 terminate at a top wall 68, and a longitudinal slot 72 splitsthe top wall 68 into symmetrical portions. The slot is defined by innersurface walls 74, which are interconnected to adjacent portions of thetop wall 68 by means of a bevelled surface 76. The inner surface walls74 terminate at a tip 78, and the inner surface 82 of the top wall 68 isconnected to the tip 78 by means of an angular surface 84.

Mounted between the inner surfaces of the side walls 64 are mountingmembers 92 which contain walls 94, extending from the inner surface ofthe side wall 64 to the inner surface wall 74, and are interconnected bya bottom wall 96. The top surface 98 of the bottom wall provides a stopwhen the printed circuit board connector is inserted therein. Further,the members 92 may be slotted as at 102, to allow insertion of apolarizing plate 104 therein. the slot 102 normally extends through tothe bevelled surface 76 for allowing insertion of the polarizing plate104 from the top of the insulating member. The bottom wall 96 containsdownwardly opening slots 112 which terminate at a shoulder 114.

As shown in FIG. 2 and as previously pointed out, after the contacts 16have been positioned in the bores 14 of the mounting member, theinsulator housing 62 is placed on the contacts. Initially, since a planealong the longitudinal axis of the housing member is parallel to a planeseparating the contacts, the housing member is moved in .a downwarddirection, as shown in FIG. 2, until the upwardly facing shoulder 38 andthe upper end 46 of the mounting portion is aligned in the insulatorslots 112. [n this portion, the tips of the housing 78 initially touchthe section 34 of the contacts. Further, it should be noted that thecontact surface of the section 34 abutting the tip 78 forms a slightacute angle with the surface 34.

Since thecontacts in the vicinity of the section 36 are adjacent to eachother, further movement of the insulator in a downward direction causesthe contacts to be spread apart, as shown in FIG. 3, and the contactsare thus preloaded at the tip. The bottom surface of the insulatormember 62 may then be secured to the top surface of the mounting member12 by conventional techniques.

As shown in FIG. 4, when a printed circuit board 122 having conductors124 thereon, is inserted into the slots 72 of the insulator member 62,the contacts 16 are electrically connected to the conductors 124.Moreover, it should be noted that the tip end 30 will ride upwardly nearthe surface 84 of the insulator housing, thus protecting the tips of thecontacts from damage when the printed circuit board is inserted.

What is claimed is:

1. A printed circuit board connector comprising:

a mounting member having a pair of rows of openings therein;

a plurality of electrical contacts mounted in said openings in opposedcontact pairs;

the contacts of each said contact pairs having mounting portionspositioned in said openings, spring portions extending upwardly at anangle from said mounting portions in a direction toward one another,oppositely bent free end sections, and transitional contacting sectionsjoining said spring portions and said end sections;

a housing member positioned over said contacts for preloading saidcontacts at said free end sections, said housing being formed with apair of spaced side walls on opposite sides of said rows of contacts,said side walls having lip portions extending downwardly from the upperportions thereof terminating in edges abutting said contact free endsections, said lip portions being spaced apart to define a printedcircuit board slot therebetween, said edges holding said contacts inpreloaded condition for engagement with a printed circuit board insertedthrough said slot, said lip portions defining surfaces extending fromsaid edges upwardly and outwardly at an angle with respect to a verticalplane passing througn said slot and at a slight acute angle with respectto the upper surfaces of said contact free end sections.

2. A connector as set forth in claim 1 wherein:

said mounting member is a planar substrate; and

said housing member is a hollow shell with said side walls opening atthe bottom thereof to permit said shell to enclose said contacts abovesaid planar substrate.

3. A connector as set forth in claim 2 wherein:

said housing has transverse walls separating adjacent pairs of saidcontacts;

downwardly opening slots formed in said transverse walls; and

said mounting portions of said contacts including laterally extendingportions above said substrate and slidably disposed in said downwardlyextending slots.

1. A printed circuit board connector comprising: a mounting memberhaving a pair of rows of openings therein; a plurality of electricalcontacts mounted in said openings in opposed contact pairs; the contactsof each said contact pairs having mounting portions positioned in saidopenings, spring portions extending upwardly at an angle from saidmounting portions in a direction toward one another, oppositely bentfree end sections, and transitional contacting sections joining saidspring portions and said end sections; a housing member positioned oversaid contacts for preloading said contacts at said free end sections,said housing being formed with a pair of spaced side walls on oppositesides of said rows of contacts, said side walls having lip portionsextending downwardly from the upper portions thereof terminating inedges abutting said contact free end sections, said lip portions beingspaced apart to define a printed circuit board slot therebetween, saidedges holding said contacts in preloaded condition for engagement with aprinted circuit board inserted through said slot, said lip portionsdefining surfaces extending from said edges upwardly and outwardly at anangle with respect to a vertical plane passing througn said slot and ata slight acute angle with respect to the upper surfaces of said contactfree end sections.
 2. A connector as set forth in claim 1 wherein: saidmounting member is a planar substrate; and said housing member is ahollow shell with said side walls opening at the bottom thereof topermit said shell to enclose said contacts above said planar substrate.3. A connector as set forth in claim 2 wherein: said housing hastransverse walls separating adjacent pairs of said contacts; downwardlyopening slots formed in said transverse walls; and said mountingportions of said contacts including laterally extending portions abovesaid substrate and slidably disposed in said downwardly extending slots.